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宝钢生产的中碳亚包晶成分钢连铸坯角横裂属于沿晶界的开裂，主要发生在８５０℃ｔ以下温度，对３个钢种连铸坯试样的高温力学性能的测定表明，在ε＝４×１０－３／ｓ应变速率下，所测钢种在熔点～７００℃范围存在两个脆性温度区域，即熔点～１３５０℃的第Ｉ脆性温度区域和８５０～７２５℃的第Ⅲ脆性温度区域，在第Ⅲ脆性温度区域，γ单相域ＡｌＮ等氮化物在γ晶界的析出和在γ＋α两相区先共析α相呈网膜状，在γ晶界的析出是造成钢脆化的主要原因。通过控制钢中氮、铝含量，采用较温和的二冷方式，使铸坯在矫直处的边角部温度避开第Ⅲ脆性温度区，铸坯的角横裂缺陷有了大幅度的降低。
The angle-transverse cracking of medium-carbon sub-peritectic steel slabs produced by Baosteel belongs to the cracking along the grain boundaries and occurs mainly at a temperature below 850 ℃ t. The determination of the high-temperature mechanical properties of three steel continuous casting billets shows that, Under ε = 4 × 10-3 / s strain rate, there are two brittle temperature zones in the range of melting point ~ 700 ℃, that is, the first brittle temperature zone of melting point ~ 1350 ℃ and the third brittle temperature zone of 850 ~ 725 ℃ In the brittle temperature region, the precipitation of nitrides, such as γ single phase AlN, in the γ grain boundary and the eutectoid α phase in the γ + α two-phase region are in the form of omentum in the third brittle temperature region, and precipitation occurs in the γ grain boundary The main reason for embrittlement. By controlling the content of nitrogen and aluminum in the steel and adopting a relatively mild second cooling mode, the corner temperature of the slab at the straightening place is avoided from the third brittle temperature zone, the angle transverse cracking defect of the slab has been greatly reduced .